Question

我创建了一个带下拉列表的导航栏。导航工作得很好。并且＆＃34;活跃＆＃34;上课可以毫无问题地转移，但不能转移到＆＃34; li＆＃34;下拉列表的元素。所有活跃的＆＃34; li＆＃34;带有边框底部的下划线。如果我导航到＆＃34; li＆＃34;元素＆＃34;下拉＆＃34;它将被加下划线，但不会被选中＆＃34; li＆＃34;下拉列表中的项目。我做错了什么？

这是我的index.html

  $(".nav a").filter(function () {
        return this.href == location.href
    }).parent().addClass("active").siblings().removeClass("active");

    $("li").click(function () {
        // remove classes from all
        $("li").removeClass("active");
        // add class to the one we clicked
        $(this).addClass("active");
    });

这里是js

Exception in Application constructor
java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
    at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Unable to construct Application instance: class gui.test.Animation
    at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:907)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$155(LauncherImpl.java:182)
    at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$161(LauncherImpl.java:819)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
    ... 1 more
Caused by: java.lang.NullPointerException: Input stream must not be null
    at javafx.scene.image.Image.validateInputStream(Image.java:1128)
    at javafx.scene.image.Image.<init>(Image.java:706)
    at gui.test.Animation.<init>(Animation.java:22)
    ... 13 more
Exception running application gui.test.Animation

提前致谢。

Answer 1

 $("li").click(function () {
   $("li").each(function(index, ele) {
        $(ele).removeClass("active");

    });
        $(this).addClass("active");
    });

在li click函数中使用jquery每个函数来删除所有活动类

如何将活动类重定向到下拉菜单？

1 个答案: